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Graviton Absorption by Non-BPS Branes

Ph. Brax
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Abstract

We consider the behaviour of neutral non-BPS branes probed by scalars and gravitons. We show that the naked singularity of the non-BPS branes is a {\it repulson} absorbing no incoming radiation. The naked singularity is surrounded by an infinite potential well breaking the unitarity of the scattering S-matrix. We compute the absorption cross section which is infrared divergent. In particular this confirms that gravity does not decouple for the non-BPS branes.

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Ph. Brax. 2001-01-12. Graviton Absorption by Non-BPS Branes. https://doi.org/10.1016/s0370-2693(01)00205-2

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